Kazamatsuri Mana

The protagonist's cousin and the younger of the two sisters. On the surface she appears to be a calm and stable girl, but she is actually hiding her irrational side. She has very good physical abilities. Because of the fact that the protagonist has albino like white hair and rude manners, she has personally taken on the role of his caretaker. The reason she ties her hair up is because the protagonist complimented her when they were young.